How do I cast a memory buffer to a swift struct

Asked Oct 04 '18 at 04:24

Active Oct 04 '18 at 04:24

Viewed 316 times

In C I am able to cast a memory buffer as a struct. This makes parsing extremely easy. How can I do the same in swift?

I have tried utilizing offset(of: ...) but it doesn't seem to pack the size into the shortest possible size, and I am unaware of a directive that informs swift to pack the memory.

I asked the question of offset(of: ...) here: Swift offset(of:) for UInt8 has 2 byte offset

asked Oct 04 '18 at 04:24

Michael Ozeryansky

7,204
4
49
61

1

Possibly helpful: https://stackoverflow.com/questions/47525922/reading-data-into-a-struct-in-swift – Martin R Oct 04 '18 at 04:54
Btw, *both* C and Swift align struct members, and just copying a C struct into a memory buffer does not “pack” the elements either. – Martin R Oct 04 '18 at 05:38
@MartinR I've marked my C structs as packed, but this attribute isn't available in Swift. – Michael Ozeryansky Oct 04 '18 at 19:26
1

Compare https://stackoverflow.com/a/39302927/1187415: *"If you depend on a specific layout, you should define the struct in C and import it into Swift for now."* Even the layout of packed C structures is preserved in Swift. – Martin R Oct 04 '18 at 19:51
@MartinR Great! Thanks. – Michael Ozeryansky Oct 04 '18 at 23:07

How do I cast a memory buffer to a swift struct

0 Answers0